<!DOCTYPE html>
<html lang="zh-hans-cn">
<head>
  <meta charset="UTF-8">
  <meta name="author" content="dongls,173110115@qq.com">
  <meta name="viewport" content="width=device-width,initial-scale=1,maximum-scale=1">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>xForm在线示例</title>
  <style>
    #loading{
      position: fixed;
      top: 24vh;
      left: calc(50% + 4ch);
      font-size: 16px;
      font-family: monospace;
      line-height: 20px;
      text-align: center;
      overflow: hidden;
      white-space: nowrap;
      width: 8ch;
      animation: typing 1.5s steps(3) infinite;
    }
    
    @keyframes typing{
      75%{width: 11ch;}
      100%{width: 11ch;}
    }
  </style>
</head>
<body>
  <div id="loading">loading ...</div>
  <div id="app"></div>
</body>
</html>